In some conventional air conditioners having a plurality of heat source units, heat source side branch liquid lines and heat source side branch gas lines of the plurality of heat source units are connected to a separately provided line unit, and the heat source side branch liquid lines and the heat source side branch gas lines are merged together inside the line unit as a refrigerant liquid junction line and a refrigerant gas junction line and connected to user units.
This line unit not only functions to integrate the aforementioned heat source side branch liquid lines and the heat source side branch gas lines into a refrigerant liquid junction line and a refrigerant gas junction line, but when some of the plurality of heat source units stop operating in response to the operational burden of the user units, the line unit also functions to accumulate refrigerant inside the stopped heat source units to prevent a shortage in the refrigerant that flows between the user units and the operating heat source units.
With this type of air conditioner, the heat source side branch liquid lines and the heat source side branch gas lines of each heat source unit can be merged together into a refrigerant liquid junction line and a refrigerant gas junction line by simply connecting the heat source side branch liquid lines and the heat source side branch gas lines to the line unit, and thus the ability to construct the air conditioner at the location in which it is to be installed can be improved (see, for example, Japanese Published Unexamined Patent Application No. H06-249527).
However, from a manufacturing viewpoint, the line unit of the aforementioned conventional air conditioner must be manufactured and stored as inventory, and thus causes costs to increase. Thus, there is a need to eliminate the line unit when seen from the perspective of manufacturing these units.